Conventionally, in an automatic transmission of the type in which a transmission mechanism for varying speeds stepwise or continuously variably is driven by hydraulic pressure, the hydraulic pressure supplied to the transmission mechanism is controlled by a pressure control unit controlled by a control circuit unit.
An automatic transmission such that a connector case is arranged in such a way as to pass through a housing for housing a pressure control unit and that a control circuit unit connected to the electric components of the pressure control unit is housed in the connector case to thereby form a connector is disclosed as one of the automatic transmissions of this type in U.S. Pat. No. 5,823,070. In the automatic transmission of this type, it is possible to realize, for example, a speed change responsive to the driving state of a vehicle by electrically connecting the control circuit unit housed in the connector case to another control circuit unit outside the housing and the electric components such as a sensor.
However, as disclosed in U.S. Pat. No. 5,823,070, when the connector case is divided into two parts and the divided parts are arranged respectively inside and outside the housing, it is necessary to electrically connect the electric components of the pressure control unit to the control circuit unit before the connector is formed and to perform the operation test of the automatic transmission in this state. For this reason, to form the connector after the operation test, it is necessary to clear the state where the electric components of the pressure control unit are electrically connected to the control circuit unit. Therefore, electric characteristics between the electric components of the pressure control unit and the control circuit unit that are obtained after the connector is formed will vary from those obtained when the operation test is performed, which will bring about a situation in which desired speed change characteristics cannot be produced.